Warm Audio WA-47
and WA-47jr
JON THORNTON warms to two new takes on a classic design

F

ounded in 2011 by Bryce Young,
Warm Audio’s tag-line (Serious
Gear, Seriously Affordable)
explains much about the
product mix and design philosophy.
Concentrating exclusively on the
analogue side of the signal path, the
company’s first product was the WA12
discrete mic pre-amp. The brash orange
colour scheme of this little box matched
its intent to provide creative colour as
well as simple gain to the signal path —
but using the highest quality
components to achieve the best balance
of price to performance.
The following five years saw the range
expand to include more mic-preamps,
compressors and EQ combinations,
some of which bear more than a passing
similarity in both design and looks to
some familiar classics. And that sincerest
form of flattery continued when Bryce
first turned his attention further up the
signal path. The WA87, launched in 2016,
was the first of Warm Audio’s mic
offerings — no prizes for guessing the
inspiration there — followed swiftly by
the WA14, inspired by the 1970s iteration
of a certain Austrian icon. It’s interesting
that Warm Audio has focussed on the
24 / Digital • April 2018

classic incarnations of what were really
studio workhorses, rather than anything
more exotic. Their latest offerings do, in a
sense, continue this school of thought.
Because, whilst Neumann’s U47 often
has an almost revered status attached to
it, it was just as much the workhorse of
its day.
Two flavours of U47-inspired
microphones are offered by Warm
Audio, differentiated chiefly by the
electronics and the physical size. Both
microphones feature the same capsule.
This is a custom (Australian)
manufactured design, based on the
centre terminated, dual diaphragm,
shared back-plate K47.

WA-47: nine polar patterns

In the ‘full-fat’ WA-47 this capsule feeds
a valve based electronics stage with
transformer coupled output, and the
whole thing is packaged in a hefty, solid
looking body that closely mirrors the
size, look and feel of the original valve
U47. There are some differences of
course. Unlike the original, polar pattern
selection is via the external supply, and
nine patterns (omni, figure—eight and
cardioid with six intermediate steps)

/ JJ Slovak 5751 tube

are available.
The manufacturer’s literature goes to
great lengths to stress the care taken in
component choice for the internals. A
Slovak Republic JJ5751 valve is
employed, offering a deliberately lower
gain than other choices might in order
to emphasise the sonic effects of the
interplay between valve, capsule and
TAB-Funkenwerk output transformer.
Even the supplied 7 pin cable that
connects the mic to the power supply
hasn’t escaped scrutiny in its effect on
overall performance, with Gotham
Audio cable and connectors used here.
The WA-47jr dispenses with the
thermionics, instead utilising FET based
transformer-less electronics mated to
the same capsule. The ‘junior’
designation is entirely appropriate here.
Unlike the WA-47, which bears a striking
visual similarity to the original, the U47jr
doesn’t ape the form factor of
Neumann’s U47 FET. Instead it looks for
all the world like its larger brethren that
has somehow been shrunk in the wash
(and shed a few pounds in the process).
Three polar patterns are available via a
stubby toggle switch at the front of the
mic, with further switches at the rear
providing a -10dB pad and a 70Hz high
pass filter.
Both microphones ship with a familiar
looking suspension mount, the only
significant difference being that the
WA-47 has sprung clamps to hold the
microphone, whilst the WA-47jr screws
into the bas e of the mount. The
WA-47jr also comes with a solid clip,
and whilst this does actually fit its bigger
brother, I’d feel a little nervous using it
support such a weighty microphone.